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    <script>
        var arr1 = [1,2,3,"D",4,5,6] ;
        var arr2 = ["A","B","C","D","E","F","G","H","I"] ; 
        var newArr = arr1.concat(arr2) ; 
        var arr3 = arr1.sort( function ( a , b ) {
            return b - a ;
        })
        console.log(arr3);
        // console.log(newArr);
        // console.log(newArr.sort());
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